1

 

                 DEPARTMENT OF HEALTH AND HUMAN SERVICES

 

                       FOOD AND DRUG ADMINISTRATION

 

               CENTER FOR FOOD SAFETY AND APPLIED NUTRITION

 

 

 

 

 

 

 

 

 

 

                     FOOD ADVISORY COMMITTEE MEETING

 

Advice on CFSAN'S Draft Report:

Approaches to Establish Thresholds for Major Food Allergens and for Gluten in Food

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                         Thursday, July 14, 2005

 

                          8:30 A.M. to 5:20 P.M.

 

 

 

 

                            Greenbelt Marriott

                              6400 Ivy Lane

                              Grand Ballroom

                        Greenbelt, Maryland 20770

                                                                  2

 

                         P A R T I C I P A N T S

 

       FOOD ADVISORY COMMITTEE STANDING MEMBERS:

 

       Richard A. Durst, Ph.D. - Acting Chairman

       Jeffrey A. Barach, Ph.D. (Industry Representative)

       Patrick S. Callery, Ph.D.

       Dennis Gonsalves, Ph.D., M.S.

       Jean M. Halloran (Consumer Representative)

       Douglas C. Heimburger, M.D., M.S.

       Margaret C. McBride, M.D.

       Mark Nelson, Ph.D. (Industry Representative)

       Carol I. Waslien Ghazaii, Ph.D., R.D.

 

       TEMPORARY VOTING MEMBERS:

 

       Petr Bocek, M.D., Ph.D. (Absent 7/14/05 Session)

       Margaret Briley, Ph.D., R.D.

       Erica Brittain, Ph.D.

       Ciaran P. Kelly, M.D.

       Soheila June Maleki, Ph.D.

       David O. Oryang

       Marc D. Silverstein, M.D.

       Suzanne Teuber, M.D.

 

       FOOD AND DRUG ADMINISTRATION:

       Robert E. Brackett, Ph.D. - Director

       Food and Drug Administration, CFSAN

 

       Catherine Copp, J.D. - Senior Policy Advisor

       Food and Drug Administration, CFSAN

 

       Steven M. Gendel, Ph.D. - Senior Scientist

       Food and Drug Administration

       National Center for Food Safety and Technology

 

       Rhonda Kane, M.S., R.D. - Consumer Officer

       Food and Drug Administration, CFSAN

 

 Marcia Moore, Food Advisory Committee, Executive Secretary

                                                                  3

 

                   P A R T I C I P A N T S (Continued)

 

       FOOD AND DRUG ADMINISTRATION STAFF:

 

       Michael M. Landa, J.D. - Deputy Director for Regulatory Affairs

 Food and Drug Administration, CFSAN

 

 

       Stafano Luccioli, M.D. - Senior Medical Advisor

       Food and Drug Administration, CFSAN

 

       GUEST SPEAKERS:

 

       Pekka Collin, M.D., M.P.H. - Professor

       University of Tampere, Medical School, Finland

 

       Catherine L. Copp, J.D.

       Policy Advisor, CFSAN, FDA

 

       Alessio Fasano, M.D. - Professor of Pediatrics

       Medicine & Physiology and Director, the Mucosal

       Biology Research Center, Center for Celiac

       Research, University of Maryland School of

       Medicine

 

       Steven M. Gendel, Ph.D. - Senior Scientist

       National Center for Food Safety and Technology, FDA

 

       Rhonda R. Kane, M.S., R.D. - Consumer Safety

       Officer CFSAN, FDA

 

       Donald Kasarda, Ph.D. - Consultant and Retired

       Senior Scientist, Agriculture Research Service,

       USDA

 

       Cynthia Kupper, R.D., C.D. - Executive Director

       Gluten Intolerance Group of North America

 

       Joseph A. Murray, M.D. - Professor of Medicine

       The Mayo Clinic of Rochester, Minnesota

                                                                  4

 

                             C O N T E N T S

 

                                                               PAGE

       Call to Order and Welcome and Introductions

                 Richard Durst, Ph.D., Acting Chairman            6

 

       Use of Gluten Thresholds

                 Catherine L. Copp, J.D., CFSAN, FDA              9

 

       Introduction to Celiac Disease

                 Joseph Murray, M.D.                             11

 

       Patient Perspectives on Celiac Disease

                 Cynthia Kupper, R.D., C.D.                      69

 

       Grains

                 Donald Kasarda, Ph.D., USDA                     84

 

       Question and Answer Session                              108

 

       Prospective Studies

                 Alessio Fasano, M.D.                           114

 

       Question and Answer Session                              146

 

       Retrospective Studies

                 Pekka Collin, M.D., M.P.H.                     161

 

       Question and Answer Session                              182

 

       International Perspectives on Gluten-Free

                 Rhonda S. Kane, M.S., R.D., CFSAN, FDA         186

 

       Question and Answer Session                              198

 

       Public Comments:

 

                 Elaine Monarch                                 212

 

                 Alice Bast                                     220

 

                 Mary Schluckabeer                              225

 

                 Tom P. Sullivan                                232

 

                 Steve Taylor                                   240

                                                                  5

 

                             C O N T E N T S

 

                                                               PAGE

 

       Overview of Approaches to Establishing

         Thresholds: Gluten

                 Steven M. Gendel, Ph.D.                        253

 

       Question and Answer Session                              257

 

       Committee Discussion:

 

                 Panel Discussion with Guest Speakers           259

 

                 Gluten and Celiac Disease - FDA Questions      287

 

                 Revisit Food Allergens                         354

 

       Adjournment

                 Richard Durst, Ph.D., Acting Chairman          363

                                                                  6

 

                          P R O C E E D I N G S

 

               CALL TO ORDER AND WELCOME AND INTRODUCTIONS

 

                 CHAIRMAN DURST:  Good morning.  I would

 

       like to call the meeting to order.  All right, I

 

       would like to welcome everyone back and also

 

       welcome new participants in our meeting this

 

       morning.

 

                 For those of you who weren't here

 

       yesterday, there is a "Conflict of Interest

 

       Statement" over on the table, if you want to refer

 

       to that at all, otherwise I would also ask again

 

       that maybe our participants or our members of the

 

       Food Advisory Committee would introduce themselves

 

       again for the benefit of those who were not here

 

       yesterday.

 

                 I am Dick Durst, professor [of]chemistry at

 

       Food Science and Technology Department at Cornell

 

       University.

 

                 Marc, would you start it off?

 

                 DR. SILVERSTEIN:  Marc Silverstein, I'm a

 

       general internist and geriatrician at Baylor Health

 

       Care System in Dallas.

                                                                  7

 

                 DR. TEUBER:  Suzanne Teuber, I am an

 

       allergist at UC-Davis.

 

                 MR. ORYANG:  I am David Oryang.  I am a

 

       risk analyst and agricultural engineer at the

 

       United States Department of Agriculture, Animal and

 

       Plant Health Inspection Service.

 

                 DR. KELLY:  Good morning.  Ciaran Kelly, I

 

       am a gastroenterologist at Harvard Medical School

 

       in Boston.

 

                 DR. MALEKI:  I am Soheila Maleki.  I am a

 

       scientist with the USDA.

 

                 DR. BRITTAIN:  Erica Brittain, I am a

 

       statistician at the National Institute of Allergy

 

       and Infectious Disease.

 

                 DR. BRILEY:  Margaret Briley, University

 

       of Texas at Austin, nutritionist.

 

                 MRS. MOORE:  Marcia Moore, I am the

 

       executive secretary for the Food Advisory Committee

 

       and the Food and Drug Administration.

 

                 DR. WASLIEN:  I am Carol Waslien,

 

       nutritional epidemiologist at the School of

 

       Medicine, the University of Hawaii.

                                                                  8

 

                 DR. BRILEY:  I am Margaret McBride, child

 

       neurologist at Akron Children's Hospital.

 

                 DR. CALLERY:  Pat Callery, West Virginia

 

       University, pharmaceutical scientist.

 

                 DR. GONSALVES:  I am Dennis Gonsalves, a

 

       scientist at USDA.

 

                 DR. HEIMBURGER:  I am Doug Heimburger, a

 

       physician and nutrition specialist at the

 

       University of Alabama at Birmingham.

 

                 DR. BARACH:  Jeff Barach with Food

 

       Products Association here, in Washington, D.C., in

 

       regulatory affairs.

 

                 DR. NELSON:  Mark Nelson with the Grocery

 

       Manufacturers Association here, in Washington,

 

       D.C., and I am responsible for scientific and

 

       regulatory policy.

 

                 MS. HALLORAN:  Jean Halloran with

 

       Consumers Union located in Yonkers, New York, and I

 

       am director of food policy initiatives.

 

                 CHAIRMAN DURST:  Thank you very much.

 

                 I would also like to remind everyone and

 

       also for our new people here at the meeting that

                                                                  9

 

       the "Charge" of the Committee is written out on the

 

       meeting document.  The most important thing is that

 

       we are focusing on the "Threshold Working Group

 

       Draft Report on Approaches to Establish Thresholds

 

       for Major Food Allergens and for Gluten in Food."

 

                 We are not here to set any kind of

 

       thresholds or discuss the labeling of these foods

 

       for allergens, but strictly to make comments on the

 

       best approaches to use for setting these

 

       thresholds.

 

                 Did I cover everything that we need to?

 

                 (No verbal response.)

 

                 CHAIRMAN DURST:  In that case, let's begin

 

       with our first presentation.  This is

 

       Catherine Copp, the policy advisor for CFSAN, FDA,

 

       on the use of gluten thresholds.

 

                         USE OF GLUTEN THRESHOLDS

 

                 MS. COPP:  I have been asked this morning

 

       to proceed with discussion on gluten and threshold

 

       levels for gluten or possible thresholds for gluten

 

       framework.  It is similar to yesterday.  I simply

 

       want to provide you with some context for the

                                                                 10

 

       evaluating the Draft Report portion that addresses

 

       gluten in food.  This is the hazard of being first.

 

                 (Slide.)

 

                 MS. COPP:  Yesterday, I mentioned the Food

 

       Allergen Labeling and Consumer Protection Act.

 

       This is a new law that Congress passed last August.

 

       Although it focuses primarily on allergens, food

 

       allergens, Congress also directed FDA to address

 

       the separate problem of gluten in food.

 

                 When I say directed, I mean that Congress

 

       has mandated that the Agency consider and then

 

       establish regulations according to a schedule to

 

       define "gluten-free" for use on food labels and

 

       also to identify the appropriate use of the term.

 

                 As with Allergens, for consumers with

 

       celiac disease, strict avoidance of gluten at

 

       levels that will elicit an adverse effect is the

 

       only means to prevent potentially serious

 

       reactions.

 

                 Accurate, complete and informative

 

       labeling on foods can help these consumers achieve

 

       their goal.  We believe that understanding

                                                                 11

 

       thresholds for gluten and having a sound scientific

 

       framework for evaluating the existence of such

 

       thresholds will help FDA develop a definition of

 

       gluten-free and identify appropriate use of the

 

       term.  That's it.

 

                 Thank you.

 

                 CHAIRMAN DURST:  Does anyone have any

 

       comments or question on Catherine's presentation?

 

                 (No verbal response.)

 

                 CHAIRMAN DURST:  Okay.  We will move on

 

       then to the presentation from Dr. Joseph Murray,

 

       professor of medicine at the Mayo Clinic of

 

       Rochester, Minnesota, on the introduction to celiac

 

       disease.

 

                      INTRODUCTION TO CELIAC DISEASE

 

                 DR. MURRAY:  Good morning, Committee

 

       Members.  I will be providing a general overview to

 

       celiac disease.

 

                 (Slide.)

 

                 DR. MURRAY:  First of all, we will discuss

 

       what is celiac disease.  We will discuss, briefly,

 

       the pathogenesis of the disease; who gets it; what

                                                                 12

 

       the treatment is, at least in a very relatively

 

       superficial fashion.  We will discuss some of the

 

       complications and compliance issues of celiac

 

       disease and a prognosis or future of celiac

 

       disease.

 

                 (Slide.)

 

                 DR. MURRAY:  Obviously, yesterday was

 

       focused on food allergies.  "Celiac disease" is one

 

       of the food intolerances that is immune-mediated,

 

       though it is not thought to be IgE-mediated; so, it

 

       comes into the non-IgE-mediated food intolerances

 

       that are mediated by an immune response.

 

                 (Slide.)

 

                 DR. MURRAY:  Where does it happen?  It

 

       happens within the smaller intestine, predominantly

 

       the proximal, smaller intestine is the workhorse of

 

       the digestive system.  It is this surface of the

 

       intestinal lining that is maximally expanded by the

 

       development of circular folds and on top of these

 

       circular folds the so-called "villi," these villi,

 

       shown here in a histological picture, which

 

       maximize the digestive surface area.

                                                                 13

 

                 It is on the surface entrocytes of these

 

       villi that most of the enzymes and in the layer

 

       immediately above that in the lumen where most

 

       digestion of the macromolecules from nutrition are

 

       broken down and then absorbed.  This is just a

 

       picture.  It looks like one of those shag-ply

 

       carpets from the 1970s.  This is a normal

 

       appearance.

 

                 (Slide.)

 

                 DR. MURRAY:  However, celiac disease is an

 

       inflammatory state of the small intestinal mucosa.

 

       It occurs in those who are genetically predisposed,

 

       and it resolves, the damage resolves, with

 

       exclusion of dietary gluten.

 

                 Here, on the left, is a normal intestine

 

       with a normal villus structure; and on the right,

 

       fully evolved celiac disease with complete

 

       destruction.

 

                 The villi are gone, not only are they gone

 

       but this entire intestinal mucosa is greatly

 

       thickened and filled with inflammatory cells.  This

 

       is where the primary site of injury occurs in

                                                                 14

 

       celiac disease.

 

                 I didn't mention it, but it is a permanent

 

       condition.  While it will heal most of the time

 

       with exclusion of gluten, the intolerance to gluten

 

       is permanent and will recur when the individual is

 

       reexposed to gluten.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, what causes celiac

 

       disease?

 

                 (Slide.)

 

                 DR. MURRAY:  We know there are two major

 

       components to this disease: the first is the

 

       genetic background of predisposition.

 

                 Much of that predisposition revolves in

 

       the HLA type, which is part of our human leucocyte

 

       antigen-recognition system.  It is how we determine

 

       self- and non-self and generate an immune response

 

       as appropriate and its interaction with

 

       environmental factors, primarily the environmental

 

       factor of gluten.

 

                 These two conspire together to produce an

 

       immune response that becomes out of control

                                                                 15

 

       resulting in inflammation, which we just showed to

 

       you, that occurs primarily in the proximal small

 

       intestine and then subsequently the consequences of

 

       this inflammation leading to malabsorption and

 

       symptoms.

 

                 (Slide.)

 

                 DR. MURRAY:  What do we know about the

 

       genetics of the disease?  For many years, we know

 

       there is a strong, familial predisposition to the

 

       disease.

 

                 If you are unlucky enough to be a

 

       monozygous twin of somebody affected with celiac

 

       disease, your concordance rate is 80 percent.  It

 

       is not 100 percent, but it is about 80 percent.  If

 

       you are a sibling of a celiac, your chance of

 

       having it is 10 percent.  If you are a child of,

 

       about 5 to 10 percent.

 

                 There is a very strong association with

 

       certain HLA molecules.  These are Class II MHC

 

       molecules but particularly two types.  First, DQ2

 

       is the predominant type that is required for celiac

 

       disease, and in some populations DQ2 is also an

                                                                 16

 

       enabling type.

 

                 These genes, however, while they are

 

       essentially required for the disease, are not

 

       sufficient alone to the development of the disease.

 

       Probably 30 to 40 percent of the Caucasian

 

       population carry one or both of these molecules,

 

       but most of them don't get celiac disease.  There

 

       are other HLA genes that are likely involved,

 

       though they have not been well elucidated and

 

       certainly not confirmed in many populations.

 

                 There are other chromosomal disorders --

 

       Down's syndrome, Turner's syndrome, and Williams

 

       syndrome -- that are associated with a greatly

 

       increased risk of developing celiac disease for

 

       reasons that are not entirely clear, but probably

 

       are associated with the increase risk of disease in

 

       those chromosomal disorders.

 

                 (Slide.)

 

                 DR. MURRAY:  Looking at the primary

 

       environmental trigger for the disease -- that is,

 

       gluten -- it is basically the storage proteins that

 

       come from these particular cultivated grasses:

                                                                 17

 

       wheat, barley, rye, and other similar grains from

 

       within those families.  Other grasses -- for

 

       example, rice, items such as corn, sorghum, millet,

 

       and probably not even oats -- are not involved in

 

       triggering the disease.

 

                 (Slide.)

 

                 DR. MURRAY:  It is the storage proteins

 

       from the endosperm compartment of the wheat kernel

 

       particularly, and those are gliadins oar glutenins

 

       that are thought to contain the antigenic moieties

 

       that trigger the disease.

 

                 (Slide.)

 

                 DR. MURRAY:  What is it about these wheat

 

       proteins?  Well, if you take wheat, as an example

 

 

       of the others, these storage proteins are uniquely

 

       high in certain amino acids, especially glutamines

 

       and prolines.

 

                 Over 30 percent of the amino acids in

 

       gliadin are glutamines.  The glutamines, of course,

 

       can be cross-linked to give the grain its

 

       resiliency.  Really the cooking ability, the

 

       ability to use wheat as such an effective way of

                                                                 18

 

       making things that stick together like bread, for

 

       example, and maintain their shape, is largely a

 

       property of these particular combinations of amino

 

       acids.

 

                 The proline sequences that contain or

 

       proline residues contained within the wheat

 

       proteins also appear to form helices, and these

 

       helices are resistant to digestion within the

 

       mammalian gut.

 

                 (Slide.)

 

                 DR. MURRAY:  This may be a key factor in

 

       what results in the likelihood of these peptides

 

       basically being maintained and becoming, then,

 

       still available for the immune system to recognize

 

       in a patient with celiac disease.

 

                 Now, gliadin molecules are presented by

 

       these HLA types to T-cells in the intestine, and

 

       T-cells that are specifically primed to respond to

 

       gluten.  There are certain gliadin molecules that

 

       have a higher affinity than others for these

 

       Class II molecules and then the T-cell receptor.

 

                 These peptides may be processed or altered

                                                                 19

 

       within the gut, perhaps, to make them more

 

       antigenic.  They may not start out very antigenic,

 

       but then they undergo some change within the gut

 

       that may make them more antigenic.

 

                 It turns out that some of these peptides

 

       that are particular immunodominant, these are the

 

       ones that are most likely to produce an immune

 

       response, that those immunodominant peptides may be

 

       digestion resistant because they contain those

 

       proline sequences that perform helix, making them

 

       relatively poorly digestible by peptidases within

 

       the gut.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, it turns out that there

 

       is a contribution to this antigenic nature from

 

       within the intestine itself, and this may well be

 

       because of this enzyme tissue transglutaminase.

 

                 This is an enzyme that is present within

 

       the gut mucosa.  It is released by cells,

 

       especially fibroblasts when they become inflamed,

 

       and it cross-links cystine residues.

 

                 It turns out that it will also act on

                                                                 20

 

       gliadin by deamidating some of those glutamine

 

       residues, some specific glutamine residues, to

 

       glutamates, making it more antigenic by deamidating

 

       that gliadin peptide and making it fit more

 

       perfectly or with a tighter affinity into the

 

       binding groove of the DQ2-HLA molecule, and, hence,

 

       producing a more vigorous immune response within

 

       the gut.

 

                 (Slide.)

 

                 DR. MURRAY:  This is a schema, a

 

       relatively simplified schema, of what I have just

 

       talked about.  We start with wheat.  You look at

 

       particularly the ethanol-soluble fraction, and

 

       gliadin is probably broken up into smaller

 

       peptides, but still of a sufficient size to produce

 

       an immune response.

 

                 It is taken up across the epithelium

 

       presented by antigen presenting cells to the

 

       T-cells.  These are T-cells that will specifically

 

       respond to gluten then producing two types of

 

       responses: a cellular response, characterized by

 

       lymphocytes producing interferon gamma and possibly

                                                                 21

 

       other cytokines.  It is probably the cellular

 

       response that leads to the "inflammatory cascade"

 

       that produces the damaged epithelium characteristic

 

       of celiac disease.

 

                 It also produces help to the B-cell side,

 

       to produce plasma cells that produce antibodies.

 

       These antibodies are directed both against the

 

       exogenous antigen gliadin and also antibodies

 

       against tissue transglutaminase or what was known

 

       as an the endomysial antibody.  It is not known

 

       what the actual pathogenic role of this is, but it

 

       is a very useful serologic or blood marker for the

 

       disease.

 

                 I mentioned about the antigen getting

 

       changed by tissue transglutaminase.  This is a

 

       little cartoon which shows the peptide derived from

 

       gluten.  If you change one specific glutamine to a

 

       glutamic acid, which could be done by tissue

 

       transglutaminase, this then binds much more

 

       tightly.  This is the HLA molecule here on the

 

       surface of the antigen presenting cell, and it fits

 

       more perfectly into the T-cell receptor, producing

                                                                 22

 

       a more potent T-cell response.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, there are other things

 

       that happen in the setting of celiac disease, and I

 

       am really touching just on the surface of many of

 

       these, but there are other things that result in

 

       this inflammation that damage the lining of the

 

       intestine.

 

                 For example, there are metallic proteases

 

       that damage the structural elements that maintain

 

       the structure that maintain villus structure.

 

       There is endothelial injury that occurs affecting

 

       the blood vessels in the villus.  There are

 

       antibodies, autoantibodies, that are produced that

 

       affect actin that are involved in the site

 

       maintaining the structure of the entrocyte itself.

 

                 (Slide.)

 

                 DR. MURRAY:  Recently, there has been work

 

       suggesting that there is a molecule called

 

       "zonulin" that may be released in the setting of

 

       celiac disease.

 

                 This is important because it opens up

                                                                 23

 

       tight junctions between entrocytes which may allow

 

       even more ready access of the antigen, the foreign

 

       antigens, between the cells into lamina propria

 

       where antigen-presenting cells can then present

 

       those peptides to the gluten-responsive T-cells,

 

       further accelerating the disease.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, I pointed out that many

 

       people, 30 percent or more of the Caucasian

 

       population, carry DQ2 or DQ8.  Virtually, the

 

       entire population are exposed to gluten, but most

 

       people don't get the disease.

 

                 There must be triggers that produce the

 

       disease.  There is evidence that suggests that

 

       gluten in the infant diet, specifically the age of

 

       introduction of gluten into the infant's diet, may

 

       be important in triggering or at least producing

 

       autoantibody markers suggestive of celiac disease

 

       early in life.

 

                 It is not clear, however, if that changes,

 

       whether you delay introduction or not whether that

 

       changes, the lifetime risk of celiac disease, but

                                                                 24

 

       it certainly seems to be important in triggering or

 

       producing evidence in childhood at least of celiac

 

       disease immune markers.

 

                 The amount of gluten in the child's diet

 

       may be important.  There are other events such as

 

       pregnancy, infection, or surgeries that may bring

 

       previously asymptomatic celiac disease to clinical

 

       presentation.

 

                 (Slide.)

 

                 DR. MURRAY:  One could speculate, and I

 

       think this is based on some data, putting data

 

       together, that one's risk for celiac disease starts

 

       with your HLA type.  Only those who carry HLA types

 

       are at risk.  You, then, are exposed to gluten.

 

       Perhaps the timing of exposure is important,

 

       developing in some individuals a sensitivity to

 

       gluten.

 

                 Then, with the interaction of other

 

       factors such as other genes other than HLA, other

 

       things that may predispose one to autoimmunity

 

       including gender and other events that may occur --

 

       gastroenteritis, aging, postsurgical or postpartum

                                                                 25

 

       changes in the immune system that may occur -- may

 

       lead to a loss of tolerance, inflammation, and

 

       subsequent malabsorption.

 

                 (Slide.

 

                 DR. MURRAY:  Don Kasarda, who is here once

 

       used the term or suggested that celiac disease was

 

       a collision between our evolution of our immune

 

       system and our ability to recognize self and

 

       non-self through the HLA system and our cultivation

 

       of wheat and these other grasses.  This collision

 

       occurs in the intestine.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, when this collision

 

       occurs and results in damage, how does it present?

 

       And who gets the disease?

 

                 (Slide.)

 

                 DR. MURRAY:  Well, this is classic celiac

 

       disease, and this is the way that I certainly

 

       learned about celiac disease.  A severe

 

       malnourished child with evidence of malnutrition

 

       often associated with the large, swollen abdomen

 

       but great muscle, terrific muscle, wasting and

                                                                 26

 

       protein-calorie malnutrition with symptoms that

 

       would occur sometime after the onset of gluten

 

       introduction into the diet, sometime between the

 

       age of six months and seven years of age: with

 

       failure to thrive; abdominal distention; anorexia;

 

       diarrhea; steatorrhea, that is the passage of

 

       malabsorptive stools laden with fat; anemia; growth

 

       failure; and vitamin deficiencies.  That was really

 

       the picture that we had of celiac disease 30 years

 

       ago.

 

                 (Slide.)

 

                 DR. MURRAY:  However, we now see celiac

 

       disease in adulthood.  In fact, celiac disease can

 

       present at any age.  Symptoms can include things

 

       such as abdominal pain, even upper-GI symptoms:

 

       heartburn, nausea, vomiting, anemia, fatigue.

 

                 There are of course patients who have

 

       symptoms of malabsorption, though not necessarily

 

       the classic, fully evolved malabsorptive picture.

 

       Steatorrhea as a presenting symptom is relatively

 

       rare, even patients may have constipation.

 

                 (Slide.)

                                                                 27

 

                 DR. MURRAY:  It can mimic other disorders

 

       such as lactose intolerance.  Indeed, lactose

 

       intolerance may be secondary to the damage caused

 

       by celiac disease.  It may mimic the symptoms of

 

       irritable bowel syndrome or symptoms of

 

       inflammatory bowel disease.

 

                 (Slide.)

 

                 DR. MURRAY:  There are specific

 

       deficiencies that can occur in celiac disease,

 

       especially the fat-soluble vitamins -- D, E, A,

 

       and K -- with their resultant syndromes from

 

       deficiencies.

 

                 Iron deficiency is especially common in

 

       celiac disease because iron is absorbed in the

 

       proximal small intestine; folate deficiency, again,

 

       because it is absorbed in the proximal small

 

       intestine; and, interestingly, B12 deficiency may

 

       be relatively common in celiac disease by a variety

 

       of mechanisms.  Other trace elements -- zinc, B6,

 

       selenium, and others -- may also be deficient in

 

       celiac disease.

 

                 While in the past we would look for

                                                                 28

 

       combinations of these, often a patient would

 

       present with many of these deficiencies at the time

 

       of diagnosis, now it is relatively uncommon to see

 

       the entire spectrum of deficiencies.  Indeed, you

 

       usually see one or two deficiencies that are

 

       clinically evident, and the others may not even be

 

       present.

 

                 (Slide.)

 

                 DR. MURRAY:  How about non-intestinal?  I

 

       have mentioned that the major site of injury is in

 

       the gut, but there are patients who will present

 

       with non-intestinal presentations which can involve

 

       into things such as the musculoskeletal system,

 

       joint pains and osteoporosis or osteomalacia;

 

       infertility or reproductive issues, delayed

 

       puberty, spontaneous recurrent abortions have been

 

       described; hematologic, which is predominantly

 

       anemia; hyposplenism is an unusual consequence but

 

       can present; and then dentition, enamel defects,

 

       can be a presenting feature.

 

                 (Slide.)

 

                 DR. MURRAY:  To focus on iron deficiency

                                                                 29

 

       anemia, which is probably one of the most common

 

       reasons that I see celiac disease, about 5 to 8

 

       percent of adults who present with unexplained iron

 

       deficiency in some studies have celiac disease.

 

                 It is especially common in those who are

 

       resistant to the use of oral iron.  If you look at

 

       individuals who are coming to gastroenterologists

 

       for endoscopy, it may be 5 to 15 percent of those

 

       patients, depending on the study, who may have

 

       celiac disease if biopsies are taken from the small

 

       intestine.

 

                 However, many of those patients are even

 

       missed because the biopsies are still not taken

 

       during routine endoscopy in patients who have got

 

       anemia in about a third to a half of patients.

 

                 (Slide.)

 

                 DR. MURRAY:  Osteomalacia or bone disease,

 

       this is an example of severe disease with

 

       pseudofractures in the pelvis of an individual,

 

       whose only presentation was osteomalacia with no GI

 

       symptoms, caused by celiac disease.

 

                 Other non-intestinal presentations include

                                                                 30

 

       neurologic or even neuropsychiatric syndromes such

 

       as neuropathy, ataxia, seizures, cognitive decline,

 

       or dementias; fibromyalgia-like syndromes or

 

       chronic fatigue syndrome-like presentations;

 

       individuals with skin and mucous membranes, there

 

       is a specific rash associated with celiac disease,

 

       a recurrent aphthous ulceration of the mouth; the

 

       dental enamel defects we mentioned.

 

                 (Slide.)

 

                 DR. MURRAY:  And, then, dermatitis

 

       herpetiformis was specifically mentioned, because

 

       this very blistering, extremely itchy skin rash

 

       that affects the extensor surfaces is a direct

 

       manifestation of intestinal gluten sensitivity.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, what about other

 

       associated conditions?  Celiac disease is

 

       associated with other autoimmune conditions.  It

 

       may be seen in 3 to 7 percent of Type I diabetics,

 

       individuals with thyroid disease, individuals with

 

       inflammatory arthritis, primary biliary cirrhosis,

 

       as examples of others; and then the congenital

                                                                 31

 

       disorders, especially those associated with

 

       chromosomal abnormalities and also selective IgA

 

       deficiency.  If you look at relatives of celiacs,

 

       it is anywhere between 5 to 20 percent, depending

 

       on how one is related to someone with celiac

 

       disease.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, beyond the symptomatic

 

       celiac disease, there are also individuals who have

 

       no symptoms, who already have fully evolved damage

 

       within their intestine, and there may be no symptom

 

       or there may not be occurring in someone with an

 

       associated disease.

 

                 This is frequent to find this in first-

 

       and second-degree relatives of patients with celiac

 

       disease.

 

                 (Slide.)

 

                 DR. MURRAY:  There is also what is termed

 

       "latent" -- well, whether it is latent celiac

 

       disease or latent gluten sensitivity -- individuals

 

       who have a positive serologic response but have a

 

       negative small-bowel biopsy.  Some of those

                                                                 32

 

       patients will go on to develop the full-blown

 

       disease, if followed, on a normal diet.

 

                 (Slide.)

 

                 DR. MURRAY:  What about the epidemiology?

 

       To summarize, while it was first identified in

 

       Europe, it occurs essentially in all populations,

 

       which could be termed Caucasian.  Its prevalence is

 

       probably somewhere between 1 in 90 to 1 in 300;

 

       however, the diagnosis rate is much lower, which

 

       would suggest a prevalence of about 1 in 2,000, if

 

       you just look at the diagnosed cases.

 

                 It is one of the most frequent genetically

 

       based diseases.  If you look at other countries --

 

       Latin America, or other areas; Africa, especially

 

       North Africa; if you look at Asian countries --

 

       there is celiac disease present in those.  The

 

       worldwide average prevalence is somewhere very

 

       close to 1 percent.

 

                 (Slide.)

 

                 DR. MURRAY:  I'm coming a little closer to

 

       home.  This is the data from Olmsted County, that

 

       we published a couple of years ago, which looked at

                                                                 33

 

       the new case identification or the incidence rate.

 

                 The solid yellow line is the new cases per

 

       100,000 in the population, which is essentially

 

       quite low and stable over many decades until the

 

       1990s and into 2000 to 2001, showing a greatly

 

       increased rate of detection of celiac disease.

 

                 If we looked at who were being diagnosed,

 

       this is the age of diagnosis by age category.  This

 

       is the incidence per 100,000 of people in that age

 

       category in the community.  You can see that the

 

       new cases being diagnosed are predominantly people

 

       between the age of 45 and 64.

 

                 The solid line indicates females; so,

 

       females are diagnosed at a rate about twice that of

 

       males of all ages.

 

                 There are a significant portion of

 

       individuals, almost a third, who were diagnosed for

 

       the first time over the age of 65.

 

                 (Slide.)

 

                 DR. MURRAY:  One can term or consider

 

       celiac disease like an iceberg.  These are a series

 

       of icebergs where the tip of the iceberg is the

                                                                 34

 

       part that has been detected, and the part

 

       underwater is the part that can be found if one

 

       screens the population.  Of note, these are numbers

 

       per thousand not percent.

 

                 Obviously, there are some places like

 

       Ireland, for instance, which is quite a big iceberg

 

       with a lot above water but also a lot below water.

 

       Finland, which this iceberg is probably even more

 

       out of the water as they have got a very active

 

       program for finding celiac disease.

 

                 This is circa 1996.  The U.S.A. iceberg is

 

       still close to a very low level of actually being

 

       diagnosed; but this number, the part underwater,

 

       has actually grown to be something very close to

 

       what you would find in Finland or Ireland,

 

       especially when one looks at, at least what we know

 

       about is really from a Caucasian population.

 

                 (Slide.)

 

                 DR. MURRAY:  One miniature study, this is

 

       one we simply looked at, Natrona County in Wyoming.

 

       This is a very isolated community.  Anybody who has

 

       been to Wyoming, there is lots of nothing for miles

                                                                 35

 

       and miles.

 

                 We were able to study about 4,000

 

       individuals from a health fair, generally healthy,

 

       and found the numbers above just under 1 percent of

 

       people who had serologic evidence for celiac

 

       disease.

 

                 Only half of them had GI symptoms.  Most

 

       of them did not have other risk factors for celiac

 

       disease, just two having family members with celiac

 

       disease.

 

                 However, these are numbers that would

 

       confirm basically the rest of the world's data that

 

       suggests that the prevalence of celiac disease, if

 

       you look for it, is probably slightly under

 

       1 percent.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, how does one make the

 

       diagnosis?  It starts with suspicion.  Serologic

 

       tests may be very effective at detecting the

 

       disease.  The intestinal biopsies are regarded as

 

       the gold standard.  Then, one ultimately gets a

 

       response to a gluten-free diet to confirm the

                                                                 36

 

       diagnosis.

 

                 (Slide.)

 

                 DR. MURRAY:  The pathology, as we have

 

       mentioned already, is a pathology of chronic

 

       inflammation within the intestine with features

 

       such as intraepithelial lymphocytes on the surface,

 

       villus atrophy or the loss of the villus surface,

 

       great crypt hyperplasia, and then characterized by

 

       being a lamina propria filled with lymphocytes,

 

       macrophages, plasma cells, and even eosinophils.

 

                 (Slide.)

 

                 DR. MURRAY:  There is however a spectrum

 

       of damage that occurs, typified here by the Marsh

 

       classification.  This is classic disease, but there

 

       are also milder forms of the disease that may be

 

       asymptomatic in most individuals.

 

                 (Slide.)

 

                 DR. MURRAY:  Our algorithm for finding

 

       celiac disease, if we have a high clinical

 

       suspicion, an individual with malabsorption, we

 

       biopsy those individuals.  If we have an individual

 

       who is at moderately increased risk, serology is

                                                                 37

 

       probably the most effective way of finding it.

 

       Though, we yet do not depend on the serology alone

 

       to detect this, there are other circumstances for

 

       alternate; serologic testing may be necessary.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, what about treatment for

 

       celiac disease, or, as one patient with celiac

 

       disease called it, "playing gluten-free roulette"?

 

                 (Slide.)

 

                 DR. MURRAY:  The nuts and bolts of a

 

       gluten-free diet, basically one needs to avoid

 

       foods that contain the offending grains: wheat,

 

       barley, rye, and the wheatlike grains of spelt and

 

       kamut.

 

                 I put down at the bottom that many corn or

 

       rice commercial cereals do not appear to be

 

       gluten-free because of their incorporation of

 

       particularly barley extract in their flavor

 

       ingredients.

 

                 (Slide.)

 

                 DR. MURRAY:  Now, one of the issues and of

 

       course the issue for today is, How much gluten is

                                                                 38

 

       too much?  We will be hearing a lot more when you

 

       hear prospective and retrospective data later this

 

       morning on this.  I am not going to dwell on it.

 

                 One thing from clinical appreciation is

 

       that symptoms are not a good indicator of gluten

 

       ingestion.  Many patients can have significant

 

       damage to their intestine, despite the absence of

 

       symptoms when they ingest gluten.

 

                 Most patients diagnosed clinically with

 

       celiac disease have never suspected that wheat or

 

       gluten products are what are precipitating their

 

       symptoms.  They may have or are often likely to

 

       have blamed other foods that they weren't able to

 

       digest because of the damage.

 

                 Antibodies such as tissue transglutaminase

 

       antibodies are really only positive of the

 

       substantial gluten contaminating the diet.  At

 

       least in my practice if somebody admits to cheating

 

       more than once a month they will like continue to

 

       have injury in their gut.  However, there is a high

 

       degree of variability in the sensitivity to gluten

 

       ingestion, at least clinically.

                                                                 39

 

                 (Slide.)

 

                 DR. MURRAY:  We will hear a little bit

 

       about Codex Alimentarius draft standards.  This,

 

       however, is still a draft, I think a Stage IV

 

       draft.  I want to put this up really to demonstrate

 

       that there is a variance between countries and what

 

       one allows.

 

                 We will hear more from our colleagues from

 

       Europe about some of the incorporation of rendered

 

       gluten-free foods which use the gluten-containing

 

       grains as a base and then remove the proteins from

 

       them.

 

                 (Slide.)

 

                 DR. MURRAY:  What about non-responsive

 

       celiac disease?  This is relatively common.  By

 

       far, the most common reason is inadvertent gluten

 

       contamination of the diet and lymphocytic colitis,

 

       pancreatic insufficiency, bacterial overgrowth, and

 

       then only a few patients have true refractory

 

       disease that no longer responds to exclusion of

 

       gluten from the diet.

 

                 (Slide.)

                                                                 40

 

                 DR. MURRAY:  There are many potential

 

       sources of contamination of the diet with gluten,

 

       which include of course commercial cereals, eating

 

       out, communion wafers, lipstick, airborne flour or

 

       starch in certain work situations, so-called "soy"

 

       sauces made from wheat, mislabeled or unlisted

 

       ingredients have been an issue, and at least

 

       allegedly some medications.

 

                 (Slide.)

 

                 DR. MURRAY:  Some ingredients that people

 

       are concerned about: seasonings and spice blends,

 

       modified food starch, malt and malt extract,

 

       modified hop extract or yeast-malts, sprout

 

       extract, dextrins, caramel color.  There are a

 

       whole bunch of things that might be derived from

 

       gluten-containing grains.

 

                 (Slide.)

 

 

                 DR. MURRAY:  What about complications

 

       associated with untreated celiac disease?  We know

 

       the mortality of symptomatic celiacs who do not

 

       comply with the diet has doubled.  The mortality of

 

       celiac disease even when it is diagnosed is also

                                                                 41

 

       double, even following out for several years after

 

       the diagnosis.

 

                 The predominant excess in death comes from

 

       GI malignancies.  There are also morbidity

 

       consequences such osteoporosis or osteomalacia,

 

       stunted growth, infertility, chronic ill-health --

 

       all of which could be prevented by early detection

 

       and treatment.

 

                 (Slide.)

 

                 DR. MURRAY:  What are the dangers of

 

       non-compliance?  The increased mortality we

 

       discussed, the osteoporosis.  Children who were

 

       diagnosed and then did not remain on a gluten-free

 

       often have osteoporosis or diminished bone density

 

       when they get to adulthood, lymphoma, other

 

       cancers, and then the psychological effects of

 

       non-compliance.

 

                 (Slide.)

 

                 DR. MURRAY:  One of the most feared

 

       complications of this are the T-cell lymphoma.

 

       This is celiac disease on this side, and the T-cell

 

       lymphoma on the other side is one of the more

                                                                 42

 

       feared complications with a very high mortality.

 

                 (Slide.)

 

                 DR. MURRAY:  However, as I pointed out,

 

       most celiac disease is probably not symptomatic, at

 

       least when we look at a cross-section of the

 

       population.  We do not know whether those

 

       identified by screening are less sick than

 

       clinically diagnosed celiac disease.

 

                 We don't know the benefit or negative

 

       effects of a gluten-free diet in those who are

 

       found by screening alone.  We don't know if they

 

       are any more or less likely to comply with a

 

       gluten-free diet.  We don't know whether

 

       intervening in those patients will actually affect

 

       their ultimate mortality.

 

                 (Slide.)

 

                 DR. MURRAY:  George Dennison Prentice

 

       said, "What come call health, if purchased by

 

       perpetual anxiety about diet, isn't much better

 

       than tedious disease."

 

                 (Slide.)

 

                 DR. MURRAY:  This comes to the future. 

                                                                 43

 

       There is, I think, a promising future in celiac

 

       disease, a variety of approaches, which I have

 

       listed, that individuals and research groups are

 

       looking at as alternates to the gluten-free diet,

 

       though none of them are really even close to

 

       clinical use.

 

                 (Slide.)

 

                 DR. MURRAY:  This is one that has been

 

       tested in patients using a lactobacillus digestion

 

       strategy, trying to reduce the potential, harmful

 

       effects of gluten.

 

                 In summary, I would like to suggest that

 

       gluten or celiac disease is common.  It has been

 

       largely unrecognized until recently.  There are

 

       many challenges that face patients and their

 

       physicians in the treatment.

 

                 The gluten-free diet is not simple.  There

 

       is widespread use of grain proteins in good, and

 

       that makes it challenging for individuals with

 

       celiac disease.  Food ingredient source

 

       identification is of great concern to patients.

 

                 Dietitians and those who counsel patients

                                                                 44

 

       with celiac disease, we are here because of

 

       regulation or potential regulations.  Defining

 

       acceptable thresholds and verification of those may

 

       be very important to patients with celiac disease.

 

                 (Slide.)

 

                 DR. MURRAY:  I finish with an aside on

 

       another food safety issue, an invitation to come to

 

       Minnesota and enjoy Joe's and have worms at the

 

       same time.

 

                 Thank you.

 

                 CHAIRMAN DURST:  Thank you very much,

 

       Dr. Murray.

 

       QUESTION-AND-ANSWER SESSION

 

                 CHAIRMAN DURST:  I would like to ask the

 

       Committee if they have any questions or discussion,

 

       and also to point out that Dr. Murray will not be

 

       able to stay around for discussion this afternoon.

 

       If there are questions, now is the time to ask

 

       them.

 

                 Doug.

 

                 DR. HEIMBURGER:  Thank you very much for

 

       that presentation.  It is very helpful.  I do care

                                                                 45

 

       for some patients with celiac disease.  As you

 

       already mentioned, one of the big questions that

 

       they have is, "What really are my risks if I play

 

       with it a little bit?  If I knowingly introduce a

 

       little bit of gluten in my diet, how absolutely

 

       obsessive do I need to be about it?"

 

                 With the mortality being primarily

 

       associated with the risk of lymphoma, what is the

 

       quality of the evidence that compliance with gluten

 

       restriction is really correlated with the risk of

 

       lymphoma?

 

                 DR. MURRAY:  The evidence, the quality of

 

       the evidence is largely observational, taking

 

       cohorts and following them, and often their

 

       self-assessment of their level of compliance.  The

 

       data is based on those cohorts.  They are

 

       predominantly referral cohorts.

 

                 The longest follow up comes from Britain.

 

       In those, there is quite a clear increased risk not

 

       just for lymphoma but other malignancies in those

 

       who are considered not to be completely compliant

 

       with the diet.  I would say the level of evidence

                                                                 46

 

       while it is not a prospective study, in retrospect

 

       in fact it appears to be reasonably strong.

 

                 DR. BRILEY:  Margaret Briley.  I would

 

       like to know what you can tell us what might be the

 

       reason for the increased detection of celiac

 

       disease?  Is the serological test the definitive

 

       reason?  What is going on with those?  It seems to

 

       be more prevalent, as you said, in our society.

 

 

                 DR. MURRAY:  I think there are probably

 

       two reasons, one is probably serologic detection

 

       has made this an acceptable diagnosis to primary

 

       care physicians, number one; and the second is

 

       suspicion, that is, the awareness of celiac disease

 

       as a possibility.

 

                 I do not believe, however, we can rule out

 

       the possibility that celiac disease is actually

 

       increasing in prevalence over time.

 

                 We don't know, but we know that there

 

       certainly were substantial increases in other

 

       inflammatory bowel diseases over the last 50 years,

 

       which may not have been accounted for by detection

 

       rates, for example.

                                                                 47

 

                 I do agree with you it is probably the

 

       sero-detection.  It is a combination of those two

 

       things, suspicion and ease of detection have made

 

       the biggest difference.  However, I would not rule

 

       out the possibility of its actually increasing in

 

       prevalence.

 

                 CHAIRMAN DURST:  Soheila.

 

                 DR. MALEKI:  Soheila Maleki.  I was

 

       wondering how long does a person that is

 

       asymptomatic go before they find they are

 

       symptomatic?  How do they usually find out?

 

                 DR. MURRAY:  First of all, we don't know

 

       when it starts.  There is one study I didn't talk

 

       about from Denver that suggested that children, if

 

       you follow children at genetic risk for celiac

 

       disease based on HLA type, that they will convert,

 

       sero convert, by about the age of seven, though

 

       most of them are asymptomatic.

 

                 It reaches all but 1 percent of that

 

       childhood cohort, the same prevalence you find if

 

       you look at adults.  The suggestion is that you

 

       have developed that celiac autoimmunity probably by

                                                                 48

 

       the age of seven.

 

                 However, the age, the median age, of

 

       diagnosis is 45 years of age.  It is likely that

 

       those individuals have some clinical disease for a

 

       long time before they present.

 

                 In our population, the most common reason

 

       for presentation is postmenopausal anemia.  Women

 

       who have anemia sometimes go a long time,

 

       especially when they are menstruating.  The doctor

 

       says that menstruating is an excuse for the anemia.

 

       Now that they are menopausal and are no longer

 

       menstruating they no longer have an excuse for

 

       their anemia, and they are referred for evaluation

 

       for the cause of anemia.

 

                 Iron deficiency anemia at least is one of

 

       the most common, but there are other things.  For

 

       example, the development of chronic GI symptoms.

 

       Largely, as the earlier questioner said, probably

 

       awareness of the possibility of this disease, with

 

       primary care doctors using sero-diagnosis to find

 

       celiac disease.

 

                 There a lot of atypical symptoms.  There

                                                                 49

 

       are reservoirs of celiac disease, the Type I

 

       diabetics, the family members of celiacs, those

 

       with chromosomal disorders.  As the doctors looking

 

       after those people become more aware of celiac

 

       disease, they are testing their patients more.

 

DR. BRILEY:  Could you speak a little bit more about

 

       the evidence that you have in regard to physicians

 

       using the serological test?  Is it a pretty common

 

       thing to do it at the very beginning of a patient's

 

       coming in with GI problems, or is it more likely it

 

       is down the road a while?

 

                 DR. MURRAY:  If you look at the data on

 

       patients’ presentation time, from presentation to

 

       diagnosis of celiac disease, it is somewhere

 

       between 8 and 11 years from the time they present

 

       to their physician with a complaint to the time

 

       their diagnosis is made.

 

                 I think that time period is now beginning

 

       to shorten, thankfully.  The serology is done close

 

       to the end of that period, so it is often only when

 

       the suspicion is generated.  Partly that is because

 

       it is not considered at the early differential

                                                                 50

 

       diagnosis of celiac disease.

 

                 It is also difficult.  It is difficult

 

       because the symptoms are not very specific.

 

       Fatigue and some bowel disturbance and a little

 

       anemia, that is not a rare syndrome or not a rare

 

       collection of symptoms you will see in individuals

 

       in our community.  It is hard to know where you

 

       look for celiac disease and when you look for it.

 

       It is often a very delayed diagnosis.

 

                 DR. BRILEY:  Is the serological test one

 

       that is pretty accurate?  Could one count on it if

 

       you did it early?

 

                 DR. MURRAY:  If you use the more modern

 

       autoimmune tissue transglutaminase test, for

 

       example, it is reasonably good.  It is not perfect,

 

       but it is quite efficient at detecting celiac

 

       disease at that level, in that period.  It is not

 

       perfect, though, but it is a pretty good test.

 

                 DR. BRILEY:  It sounds like we need to do

 

       some education, then.

 

                 DR. HEIMBURGER:  A follow up to that --

 

       Doug Heimburger -- what is currently understood to

                                                                 51

 

       be the sensitivity specificity of anti-tissue

 

       transglutaminase antibodies?

 

                 DR. MURRAY:  Depending on the study, most

 

       studies suggest that the sensitivity of tissue

 

       transglutaminase for celiac disease is in the high

 

       90 percent, so the high 90s.

 

                 The specificity is probably also in the

 

       mid- to high 90s, so quite effective when you are

 

       looking at a population you are suspicious of the

 

       disease.

 

                 DR. BRILEY:  One more question.

 

       Margaret Briley.  Do we have any data that shows

 

       the celiac patient also maybe has been identified

 

       with a lactose intolerance?  Is there anything that

 

       combines those two that you would know or does

 

       that--?

 

                 DR. MURRAY:  The combination is probably

 

       the damage that is caused by celiac disease, the

 

       damage to the entrocytes affects your disaccaridase

 

       including lactase throughout the surface of the

 

       small bowel, and, hence, you get a secondary

 

       lactose intolerance.

                                                                 52

 

                 In general, if you think of the genetic

 

       basis or the ethnic groups that are involved,

 

       celiac disease tends to hit those of European

 

       extraction more so.  I know that population will

 

       tend to retain their lactase activity for longer.

 

                 If you look at Subsaharan Africans, for

 

       example, we don't know actually what the prevalence

 

       of celiac disease is in Subsaharan Africans, but

 

       they are individuals who tend to lose their

 

       lactase.

 

       Genetically, they are probably separate, but they

 

       come together because of secondary lactase

 

       deficiency caused by the damage in celiac disease.

 

                 DR. NELSON:   Thank you, Dr. Murray.  That

 

       really was a very interesting presentation.  I

 

       think the last time I studied this was 30 years

 

       ago.

 

                 CHAIRMAN DURST:  Identify yourself,

 

       please.

 

                 DR. NELSON:  Mark Nelson.  I wanted to

 

       touch base on the couple of slides where you talked

 

       about how much gluten is too much and the proposed

                                                                 53

 

       Codex definition for gluten-free foods.

 

                 You had a question mark after the

 

       threshold for damage being 20 to 100 milligrams per

 

       day, and I guess that is similar to the naturally

 

       gluten-free foods the Codex proposed.

 

                 Then, it goes on to talk about cheating is

 

       greater than once per month.  Also, is there an

 

       issue of cumulative exposure, 20 milligrams per

 

       day, or is the cheating an excursion of whole wheat

 

       crackers, for example?

 

                 DR. MURRAY:  Well, first of all, the

 

       comment on cheating that is what the patients tell

 

       me, those patients who will admit to gross

 

       cheating, that is, eating a piece of bread or a

 

       cookie or cake, which is what I regard as an

 

       obvious source of gluten.

 

                 However, that may reflect some other

 

       background, but a lack of detail of care, for

 

       example, attention to detail in the rest of their

 

       diet, maybe what they are not telling us.  That

 

       only applies to what they have told me.

 

                 The issue of actual threshold, I have a

                                                                 54

 

       question mark after that because we will hear a lot

 

       more detail, science, about threshold testing for

 

       thresholds of gluten contamination.

 

                 The intermittent contamination, once a

 

       month obvious contamination.  Something that is, to

 

       some degree, under the patient's control with

 

       appropriate education and exposure to information

 

       then essentially it is under their control.

 

                 It is the low-level contamination on a

 

       regular basis from sources they are not aware of,

 

       and those are the patients that I see that make up

 

       the majority of the patients I see who have

 

       difficulty.  They are coming to me because they are

 

       trying to be gluten-free, but they are having

 

       contamination of their diet on a daily basis,

 

       probably a relatively small amount.  We will hear a

 

       lot more about the threshold, the actual testing of

 

       the threshold using that type of low-level daily

 

       contamination.

 

                 DR. MALEKI:  Soheila Maleki.  Is there an

 

       adult onset or spontaneous development of celiac

 

       disease, or does this have to come with a genetic

                                                                 55

 

       component and hereditary?

 

                 DR. MURRAY:  It probably only occurs in

 

       people who have that HLA or genetic type.  You have

 

       to have it.  However, that is 30-plus percent of

 

       the Caucasian population.

 

                 Can it start first in adulthood?  We have

 

       very little data on that.  The only data is the

 

       stuff I have mentioned, looking at children and

 

       showing about 1 percent by the age of seven or

 

       eight, positive by the age of seven or eight, the

 

       same prevalence if you look at adulthood.

 

                 There are a few cases of what we call

 

       "latent celiac disease," individuals who have got

 

       antibodies with apparently normal small intestinal

 

       biopsies as adults, then go on over a space of

 

       years to develop full-blown celiac disease within

 

       years of that initial identification of a positive

 

       serology.  Those are very rare cases that have been

 

       found.

 

                 Of course, if you find somebody who

 

       suspects they have got a problem, they ought to

 

       change their diet anyway, and that changes

                                                                 56

 

       everything.  There is very little data, I think, to

 

       be sure of whether it first occurs, starts, in

 

       adulthood.

 

                 If you look at the age of diagnosis, your

 

       eighth or ninth decade can be the first time that

 

       you are diagnosed with celiac disease.  A lot of

 

       those patients have suspicious symptoms going back

 

       many years.

 

                 DR. BRITTAIN:  Erica Brittain.  Can you

 

       quantify the level of damage?  Is that only

 

       possible with the biopsy, and is that very

 

       invasive?

 

                 DR. MURRAY:  You can -- well, if you take

 

       biopsies, you can quantify the degree of injury.  I

 

       showed that slide which shows a spectrum of injury.

 

       It tends to be variable, even within the same

 

       individual.  It started in the first part of the

 

       small intestine and extends a variable distance

 

       down the small intestine.

 

                 There has really only been one study,

 

       which was done in the early 1960s, of taking

 

       multiple biopsies down the intestine -- a handful

                                                                 57

 

       of courageous volunteers.

 

                 It is not clear that there is a

 

       correlation between the extent of injury and the

 

       severity of symptoms.  In fact, we don't know how

 

       to predict the occurrence of symptoms in patients

 

       with celiac disease, so that is a "black box."

 

                 DR. BRITTAIN:  You are saying there is

 

       really no simple way to quantify the extent of

 

       damage?  There is nothing that would correlate with

 

       these multiple biopsies?

 

                 DR. MURRAY:  Some people have suggested

 

       that the level of the antibodies, the tighter the

 

       antibodies might correlate:  The higher, the

 

       tighter, maybe the more severe the injury to the

 

       intestinal biopsies.

 

                 When we take a biopsy of the intestine, we

 

       are sampling a tiny fraction of a percentage of

 

       1 percent, a fraction of 1 percent, of the

 

       intestinal lining.  We have tried to look using

 

       other imaging techniques to assess the extent of

 

       injury.  Using some of those techniques seems to be

 

       very variable between individuals, and it doesn't

                                                                 58

 

       seem to predict their symptoms.

 

                 Really right now it is a yes or no issue:

 

       yes, they have celiac disease; or, no, they do not.

 

       It is very hard to measure the severity of the

 

       disease.

 

                 We can look at the severity of

 

       consequences: have they developed osteoporosis,

 

       what their bone density is, have they lost a lot of

 

       weight, whether they have severe malabsorption

 

       based on fat malabsorption in their stool.  We have

 

       got other measures to look at the consequences or

 

       impact of the disease, those we can assess.

 

                 DR. BRITTAIN:  Do you think that it would

 

       correlate with the intestinal damage?  Not

 

       necessarily?

 

                 DR. MURRAY:  We have tried.  I would say

 

       that the data is not very good on that.  People

 

       with very mild injury may be more likely to be

 

       asymptomatic, but the data is not sound.

 

                 CHAIRMAN DURST:  Suzanne.

 

                 DR. MALEKI:  Suzanne Teuber.  I had a

 

       question about the neurologic presentations.  I

                                                                 59

 

       have read some on screening of pediatric

 

       populations, but with adults how often does it

 

       present as dementia without it being diagnosed as a

 

       GI problem?  Is this something we should be adding

 

       to dementia screening?

 

                 DR. MURRAY:  It is probably relatively

 

       rare.  In fact, I think there has only been one

 

       good study.  Maybe Dr. Collin, who is here as a

 

       speaker later, has done a study and has looked at

 

       and reported on that.

 

                 We occasionally see cognitive decline at

 

       the time of diagnosis, but there is really no good

 

       epidemiologic study to address that.  Some of the

 

       other presentations, peripheral neuropathy, for

 

       example, or ataxia, there is more data on it.  Many

 

       neurologists are beginning to include celiac

 

       disease as part of their differential diagnosis for

 

       those syndromes.  Good epidemiology data is

 

       relatively small, very little data.

 

                 CHAIRMAN DURST:  Ciaran.

 

                 DR. KELLY:  Ciaran Kelly.  This is

 

       actually more clarification than a question.  Dr.

                                                                 60

 

       Murray is quite correct that there isn't a measure

 

       of either severity of intestine abnormality or even

 

       height of antibody levels that reliably reflects

 

       the degree of injury or correlates closely with

 

       symptomatology.

 

                 However, with treatment one can use a

 

       decline in antibody levels as a crude indicator of

 

       at least reduced exposure to gross amounts of

 

       gluten.  It is not a very sensitive indicator, but

 

       it is useful.  Of course, with repeat biopsy, if

 

       the histology has revered to normal, that of course

 

       can be used.  However, the less invasive test of

 

       following antibody levels is used clinically to

 

       follow response.

 

                 DR. MURRAY:  Quite right.  I think you

 

       will agree, Joe.

 

                 DR. KELLY:  If the antibody levels aren't

 

       dropping, that is used as an indication that the

 

       patient is successfully on a gluten-free diet.

 

                 DR. BRILEY:  Margaret Briley.  Can you

 

       give us any idea of any behavior data that you may

 

       have received from your patients regarding their

                                                                 61

 

       willingness to try foods that are not gluten-free

 

       labeled?

 

                 DR. MURRAY:  Oh, well, there are many

 

       different attitudes among patients with regard to

 

       what they want to eat or what they are afraid to

 

       eat.

 

                 I advise my patients to be prudent, that

 

       they try to select things based on identification

 

       of ingredients, source ingredients, not containing

 

       things contained from gluten, the use of substitute

 

       grains that are gluten-free.

 

                 Many patients are quite willing to do that

 

       on their own.  Many of them use support group

 

       information where maybe a group has cooperatively

 

       contacted manufacturers who in good faith provide

 

       information on their source ingredients.

 

                 There are some patients who are entirely

 

       paranoid about it, and want to obtain a kit to test

 

       the food.  I don't know that we've got a very

 

       effective kit yet for testing food for gluten

 

       contamination.  There are many different attitudes.

 

                 Fear is a major concern among my patients.

                                                                 62

 

       I mean, fear of even the slightest potential, not

 

       even actual but potential contamination.  This can

 

       verge on, "Do we avoid taking prescription

 

       medications for things like hypertension?"

 

       resulting in life-threatening changes to their

 

       medication regimens because of fear of

 

       contamination.

 

                 I would say fear is a major part or a

 

       major influence on the quality of life.  We will

 

       hear more I think shortly on the impact of a

 

       gluten-free diet on patients' lifestyles a little

 

       later.  Certainly that does affect a substantial

 

       portion of my patients.

 

                 Patients go through a substantial grief

 

       reaction and feel socially isolated because of

 

       their difficulty of interacting with society,

 

       because so much of our society activities or social

 

       activities revolve around food.  There is that

 

       safety sense of insecurity, which I think pervades

 

       or affects many patients with celiac disease.

 

                 DR. BRILEY:  Thank you.

 

                 CHAIRMAN DURST:  Soheila.

                                                                 63

 

                 DR. MALEKI:  Well, I just want to know if

 

       there are any coordinated studies for a

 

       determination of thresholds?  I know you mentioned

 

       the level of PPMs.  Do you know of any studies?

 

                 DR. MURRAY:  There are and you will hear

 

       about them.  There are both retrospective and

 

       prospective studies, and you will be hearing some

 

       data on those later this morning.

 

                 CHAIRMAN DURST:  I have one question --

 

       Dick Durst -- on the biopsy and histological

 

       studies to see the morphology, morphological

 

       changes, you showed from the shag rug.  I am just

 

       curious whether just one of these cameras you can

 

       swallow would be able to detect those kind of

 

       changes without having to go through a biopsy?

 

                 DR. MURRAY:  Yes, you can detect them.

 

       Nobody would suggest that it would replace the need

 

       for biopsies to make the diagnosis.  There is

 

       really relatively little published data on it.

 

       There has been a paper suggesting that you can see

 

       those changes.  With a magnified view, you can see

 

       with a capsule.

                                                                 64

 

                 Yes, I think you can identify those

 

       changes in a lot of individuals with celiac

 

       disease, maybe all of them.  Although, I really

 

       can't comment more on that, because it hasn't

 

       really been studied in any great detail.

 

                 CHAIRMAN DURST:  Erica.

 

                 DR. BRITTAIN:  Erica Brittain.  Do you

 

       have any insight about the cumulative effect of

 

       decades of low levels, very, very low levels of

 

       gluten exposure?  Certainly, we are going to have

 

       to think about what chronic exposure could do when

 

       we talk about the thresholds.  Can you provide any

 

       insight into that?

 

                 DR. MURRAY:  Probably the best clinical

 

       insight I can give are individuals who I see who

 

       were diagnosed 20 years ago and have not come back

 

       to medical attention in 20 years.  I see those

 

       patients maybe every week.

 

                 I would see somebody who is diagnosed 20

 

       years ago, and they got instruction at that time

 

       that allowed them to eat things like barley malt or

 

       that people weren't really instructed about some of

                                                                 65

 

       those rice or corn cereals that may have contained

 

       malt, for example.

 

                 Those patients come back with anemia,

 

       chronic GI complaints, maybe not as severe as they

 

       had initially, but they certainly have accumulated

 

       some health morbidity over those 20 years.  Some of

 

       them will come back with frank lymphomas and will

 

       end up with a mortal complication of their celiac

 

       disease.

 

                 Yes, at least my clinical observation is

 

       that I frequently see individuals with problems

 

       that we get rid of, once they now move to a much

 

       more strict gluten-free diet, by eliminating those

 

       things -- largely, because in 20 years they didn't

 

       go back and get more education and realize that you

 

       had to exclude those minor ingredients.  That is

 

       one way of looking at the effects of decades'

 

       accumulation of low-level contamination.

 

                 CHAIRMAN DURST:  Dick Durst again.  On

 

       your slide that showed the various causes, the

 

       different grains, and so on, I believe you

 

       indicated oats was not one of the causes.  Could

                                                                 66

 

       you expand on that?

 

                 DR. MURRAY:  We will hear a little more, I

 

       think, from Dr. Collin on that issue.  While oats

 

       had been thought to be one of the offending grains

 

       in things done in the fifties and sixties, it turns

 

       out from recent very well-done studies that it

 

       doesn't appear to impair the healing of the

 

       intestine in newly diagnosed celiac disease.  It

 

       doesn't seem to result in a significant worsening

 

       of production of damage in patients who are already

 

       diagnosed with celiac disease.

 

                 For the vast majority of celiacs, it is

 

       probably safe in its native, pure form.  However,

 

       there are some sequences within oats that can

 

       produce an immune response, at least in vitro, in

 

       lymphocytes derived from a few celiacs.

 

                 It is not an absolute.  There may be some

 

       individuals with celiac disease that can respond to

 

       oats, both in the laboratory test and possibly also

 

       clinically there are a few.

 

                 There are probably a relatively small

 

       minority of celiacs in which that occurs.  A bigger

                                                                 67

 

       concern is the issue of contamination of oats with

 

       other grains that are well recognized to cause

 

       injury.

 

                 CHAIRMAN DURST:  Marc.

 

                 DR. SILVERSTEIN:  Marc Silverstein.  I

 

       would like to inquire about the potential

 

       subsequent lifelong increased risk of GI cancers.

 

       I presume that the risk is predominantly small

 

       bowel, but I wonder if there is any increased risk

 

       of colorectal cancer?

 

                 Then, what are your thoughts about whether

 

       there is sufficient risk that patients with celiac

 

       disease should be in some sort of surveillance

 

       program for early detection of GI cancer?

 

                 DR. MURRAY:  Clarifying the risk of

 

       cancers, it is particularly visceral cancer but

 

       also includes: esophageal cancer, non-Hodgkin's

 

       lymphoma of any site not just the intestine, and

 

       probably also B-cell lymphomas, as well as the

 

       T-cell lymphomas, small-bowel carcinoma.

 

                 There is a greatly increased relative risk

 

       of small-bowel carcinoma.  Of course small-bowel

                                                                 68

 

       carcinomas is a very rare disease to begin with, so

 

       the lifetime risk of dying of a small-bowel cancer,

 

       even in a celiacs, is still relatively small.  The

 

       data on colon cancer is mixed.  There is some that

 

       suggests there is an association; and some, that

 

       does not.

 

                 When you look at other causes of

 

       mortality, even non-cancer causes of mortality such

 

       as infections, neurologic disorders and chronic

 

       lung infections, there are other excesses of

 

       mortality that occur in patients with celiac

 

       disease.

 

                 There are some reductions in cancer

 

       mortality.  It appears, at least there is a

 

       suggestion, that breast cancer may be less common

 

       in celiac disease than non-celiac disease.  There

 

       were a couple of suggestions that lung cancer might

 

       be less common in celiac disease than in non-celiac

 

       disease.

 

 

                 Now, whether there is some competing issue

 

       like smoking may be less common in celiac disease

 

       than non-celiac disease, so there may be some other

                                                                 69

 

 

       competing issues that are involved.  Body size may

 

       make a difference.  It may be another confounding

 

       issue that confounds or is a competing risk for

 

       malignancies.

 

                 While small-bowel cancers and lymphomas

 

       are the two that have the greatest relative risk,

 

       it is a small, absolute risk because of the

 

       relative rarity of those cancers.

 

                 CHAIRMAN DURST:  Do we have any further

 

       questions for Dr. Murray?

 

                 (No verbal response.)

 

                 CHAIRMAN DURST:  Thank you very much.

 

                 Our next speaker is Cynthia Kupper, who is

 

       the executive director of the Gluten Intolerance

 

       Group of North America who will present on patient

 

       perspectives on celiac disease.

 

                  PATIENT PERSPECTIVES ON CELIAC DISEASE

 

                 MS. KUPPER:  Good morning.  I am a

 

       dietician, not a doctor.  I appreciate the honorary

 

       doctor status.

 

                 My job here today is to give a face for a

 

       person with celiac disease.  I have been tasked

                                                                 70

 

       with letting you know who they are, letting you

 

       know how they get their information and education,

 

       and then also providing you with some information

 

       about labeling that they have.

 

                 (Slide.)

 

                 MS. KUPPER:  First of all, living with

 

       celiac disease is very difficult.  It is a chronic,

 

       lifelong condition, as you have heard, and people

 

       find this to impact greatly their quality of life.

 

                 Forty-four percent of the patients in a

 

       Canadian study say that the diet is very difficult

 

       to follow.  In fact, there are some studies that

 

       suggest that the compliance with the diet can be as

 

       low as 50 percent in teenagers but probably ranges

 

       around 70 percent compliance.

 

                 Eighty-four percent of these patients in

 

       Canada suggested they have a difficult time

 

       determining what is gluten-free and what is not.

 

       They don't travel, and they don't eat out.  It

 

       impacts their family life and their career.

 

                 If you have celiac disease and are an

 

       X-ray technician, oftentimes you change careers

                                                                 71

 

       because sometimes the X-ray slides are dusted with

 

       flour.  Chronic exposure could impact your quality

 

       of life.

 

                 (Slide.)

 

                 MS. KUPPER:  I did a study online of 620

 

       patients a few months ago.  In response to that

 

       study, 75 percent of them said that they can tell

 

       the difference between a gluten reaction and other

 

       intolerance or a food allergy.

 

                 When they discussed their reaction

 

       symptoms, they ranged from anaphylaxis, which is

 

       not a gluten reaction for celiac disease, to

 

       delayed reactions which could impact any aspect of

 

       their GI and other health systems, body systems.

 

                 The average time to reaction was somewhere

 

       between four to eight hours, but some of them

 

       complained of immediate, almost allergic type

 

       responses, and many of them said that their

 

       responses or the symptoms that they had would last

 

       for several days.

 

                 Keep in mind, there is no medication we

 

       can give them to make this go away, so they just

                                                                 72

 

       have to let it work its course.  This is really

 

       disturbing to me.

 

                 (Slide.)

 

                 MS. KUPPER:  As a dietitian, patients do

 

       not rely on medical communities and professionals

 

       for their information.  They rely primarily on

 

       support groups.

 

                 Actually, the Internet should probably be

 

       the first one, because they are Internet savvy.

 

       They have been out there and they have gotten all

 

       kinds of information before they ever see a

 

       dietitian.  Not only do they get information from

 

       the Internet and the support groups, but there are

 

       list serves and chat groups that they belong to.

 

                 These can be very useful tools for a

 

       person with celiac disease.  However, they also

 

       provide some very frightening and unreliable

 

       information that the patients will hold onto as if

 

       it were gospel.  Then, they work with self-help

 

       books as well.

 

                 Unfortunately, doctors, and especially

 

       dietitians, are seen as unreliable.  It is sad for

                                                                 73

 

       me to say that as a dietitian my profession doesn't

 

       get this disease.  They also treat it like it is a

 

       rare thing, and they don't know anything about it.

 

       In the United States, I can tell you that there is

 

       probably a handful of dietitians who would be

 

       considered experts in celiac disease.

 

 

                 Doctors don't get much more respect,

 

       primarily because it has taken so long for the

 

       patient to get a diagnosis that the patient has

 

       lost faith.

 

                 Then, they will go to research facilities

 

 

       like the University of Maryland, Chicago, and

 

       New York, or the Mayo Clinic.  Lastly, they will go

 

       to medical Web sites.  The bulk of our information

 

       is coming from potentially unreliable and

 

       non-research-based sites.

 

                 (Slide.)

 

                 MS. KUPPER:  The consumers perceive that

 

       gluten exposure levels -- the question was asked to

 

       me, "What do consumers believe about gluten

 

       exposure?  Are they concerned about the health

 

       risks?"  The answer is yes and no.

                                                                 74

 

                 On the study that I did, it depended upon

 

       their confidence of the labeling, and it depended

 

 

       on whether they accepted testimony or accepted

 

       research.  There is a group of celiacs, as

 

       Dr. Murray suggested, who really don't want to

 

       listen to what research suggests.

 

                 As you move forward, with not only

 

       establishing how you are going to determine the

 

       threshold but what that threshold will be, you will

 

       have a fight in the celiac community for a lack of

 

       education and understanding of research.

 

                 Consumers oftentimes also have an

 

       inability to correctly interpret research findings.

 

       These are people who have just enough medical

 

       knowledge to be dangerous, so they don't have a

 

       full understanding of the terminology they are

 

       talking about.

 

                 There is this constant perpetuation of

 

       misinformation.  I don't know how many times when

 

       we try to bury something that is inaccurate it gets

 

       dug up.

 

                 (Slide.)

                                                                 75

 

                 MS. KUPPER:  There are varying levels of

 

       gluten sensitivity, as you heard, too.  There is

 

       the perception that gluten is poison.  Not unlike

 

       the allergy people that we heard from yesterday,

 

       this is a huge issue to the celiac consumer.

 

                 They believe most of the time that when

 

       their gut hurts it is from gluten not from

 

       something else.  Consequently, we are trying to

 

       help the patient understand that not everything

 

       that makes their gut hurt is gluten.

 

                 As Dr. Murray said, there is a huge fear

 

       reaction.  If I had to put a psychological label to

 

       a group or at least a portion of the celiac

 

       community, they are filled with fear and a little

 

       bit paranoid about what they can and can't do.

 

                 How do we define "gluten-free" in the

 

       U.S.?  This is a really interesting question.  Of

 

       the consumers, only 19 percent realize that there

 

       is no definition right now for gluten-free in the

 

       U.S.  Many of them define that the true definition

 

       is zero.  This is a problem -- a lot don't know.

 

                 (Slide.)

                                                                 76

 

                 MS. KUPPER:  When I ask the question, "Do

 

       you trust gluten-free labeling?"  It was

 

       interesting, too, because most of the people say

 

       they do trust it.  However, when you ask them if

 

       they ever had a reaction to a product labeled

 

       gluten-free, you can see that up to 50 percent

 

       suggested that they might have had a reaction to a

 

       gluten-free product.

 

                 When I talk to manufacturers that

 

       manufacture only gluten-free products and ask them,

 

       "Do you test, and what do you test to," many of

 

       them are using older testing methods not the newer

 

       testing methods, the monoclonal tests that we

 

       talked about yesterday.

 

                 Some of them tested 200 parts per million,

 

       some of them tested 20 parts per million, some of

 

       them tested no detectible.  For the gluten-free

 

       consumer today, the label "gluten-free" really has

 

       no meaning.

 

                 (Slide.)

 

                 MS. KUPPER:  Again, the gluten-free

 

       consumer is compulsive about their medical needs. 

                                                                 77

 

       This is their only treatment.  It is often referred

 

       to as our drug of choice.  There is nothing else we

 

       can do, except to follow a strict gluten-free diet.

 

                 They have very limited trust in the

 

       manufacturing industry.  They believe that labels

 

       that say "may contain" and different things like

 

       that need to be distrusted.  When they call the

 

       manufacturers, they are not quite sure that they

 

       are getting the right answer all the time.

 

                 Also, they have a limited understanding of

 

       what good manufacturing practices really mean, so

 

       they are always questioning what the manufacturer

 

       will say.  Yet, at the same time they want

 

       accountability and they want reliability.

 

                 They may translate information to the

 

       extreme.  Let me give you an example.  A few months

 

       ago on one of the list serves, someone put out a

 

       message about bottled water being gluten-free.

 

                 That got taken in a week's time to the

 

       point where consumers were calling asking why water

 

       had gluten in it, and how dare the food industry do

 

       that to them.  The reality is it never did.

                                                                 78

 

                 A company, out of the graciousness of

 

       their heart, put it on a list of gluten-free

 

       products, and from that the consumer decided that

 

       every other bottled water had gluten in it.  This

 

       is the extreme that the consumer can go to.  Again,

 

       they don't find descriptive labeling helpful at

 

       all.

 

                 The changes that can occur in ingredients

 

       in manufacturing processes make it difficult for

 

       this consumer group to know what they can have.

 

       The term "modified food starch" usually means

 

       cornstarch, modified cornstarch, in this country.

 

                 However, if the manufacturer determines

 

       that wheat starch is cheaper in the fall and they

 

       switch and the consumer has determined that this

 

       product is gluten-free, now they are in trouble if

 

       they don't recheck.

 

                 When you talk to the food industry, you

 

       will find that their calls have dramatically

 

       increased over the last 2 to 5 years of consumers

 

       calling in, and 90 percent of the questions do not

 

       have to do with other allergens but have to do with

                                                                 79

 

       gluten.

 

                 (Slide.)

 

                 MS. KUPPER:  When the consumer asks the

 

       question about gluten, the problem is that they are

 

       asking the wrong question.  The consumers believe

 

       that if they don't have effective labeling how can

 

       anybody possibly know that they are going to be

 

       able to be healthy and protect themselves.

 

                 They want to know that if you call a

 

       company they are really giving you the right

 

       answer, and they are just never confident about

 

       that.  Oftentimes, when the company answers too

 

       quickly, they get suspicious.

 

                 Oh, I've had that experience.  I will call

 

       on a product and I'll say, "I need to know the

 

       source of the modified food starch."

 

                 "Oh, you're talking about gluten?"

 

                 "Yes.  Tell me the source of your modified

 

       food starch.  Let me make that decision about

 

       whether I'm talking about gluten."  That makes a

 

       consumer suspicious.

 

                 Finally, you know, if a person eats a

                                                                 80

 

       gluten-free food and they get sick, whether it is

 

       related to gluten ingestion or not, they have

 

       determined that they can't trust that company any

 

       longer.

 

                 Again, these list serves and chat groups,

 

       I have seen them take small companies out of

 

       business because of the spreading of rumors --

 

       which are probably unfounded.

 

                 (Slide.)

 

                 MS. KUPPER:  In closing thoughts, I really

 

       encourage that through this entire process related

 

       to labeling thresholds, that we be talking a common

 

       language.

 

                 Let me use the example of threshold.

 

       Yesterday, as I listened to Anne Munoz talk about

 

       thresholds for allergens, I realized that we have

 

       three different definitions of thresholds -- or

 

       tolerance, excuse me.  I want to use the word

 

       tolerance.

 

                 The consumer says, "Tolerance is zero."

 

       What that means is they think there should be zero

 

       gluten in their food.

                                                                 81

 

                 The medical community says "zero

 

       tolerance."  For them that means, you should be on

 

       a strict diet, and you should never cheat.

 

                 The manufacturing industry wants to know

 

       where that is.  Is it 20?  Is it 200?  They know it

 

       is not zero.

 

                 We are not talking the same language.  The

 

       consumer needs to know that the manufacturer and

 

       the industry or the legal ramifications around any

 

       labeling are all using common terminology in a

 

       language they can understand.

 

                 Education is a huge component.  As much as

 

       I am a supporter of this regulation and this law,

 

       one of the things that is going to happen, as you

 

       heard yesterday in discussions about soy lecithin

 

       and other ingredients, it is going to become a bag

 

       of worms.  For the consumer, it is going to be very

 

       confusing, and we need to have an education

 

       component as part of the new labeling laws.

 

                 I encourage you, too, although you heard

 

       it yesterday and you will probably hear it today,

 

       too, we know that there is no testing kit available

                                                                 82

 

       that tests to zero.  We know, as you will probably

 

       hear later, that it is probably an impracticality

 

       or unnecessary to even go there.

 

                 I implore that when you set a threshold

 

       method and testing methods, when you set the

 

       threshold level, that it be reasonable and

 

       something that meets the health needs of the

 

       consumer but also allows the industry to meet the

 

       need.

 

                 (Slide.)

 

                 MS. KUPPER:  As they found out in

 

       Australia, when you set zero as the tolerance level

 

       and as the magic number for food manufacturers, a

 

       lot of gluten-free products that patients used no

 

       longer can be labeled gluten-free.  Now the

 

       consumer is once again confused and outraged.

 

                 CHAIRMAN DURST:  Thank you very much.

 

                 Do we have any questions for our speaker?

 

                 Yes, Jeff?

 

                 DR. BARACH:  Hi.  Thank you.  Jeff Barach

 

       with Food Products Association.  If I interpret

 

       what you said correctly, you were talking about the

                                                                 83

 

       consumer really doesn't find descriptive labeling

 

       very helpful in the case of gluten-free.

 

                 I assume then the consumer would go to the

 

       ingredient list or the 800 numbers or their

 

       internal chat groups to find out whether the

 

       product really is gluten-free or not.  Am I

 

       interpreting that right?  Your constituency does

 

       not want gluten-free labeling?

 

                 MS. KUPPER:  I would say that is probably

 

       right, that is the message I got from the survey.

 

       In fact, they found that labels that say "may

 

       contain" or "processed in a plant with" really is

 

       frightening to them.  They will look at a product

 

       like that, and they will simply avoid it.

 

                 They do go to chat rooms and there are

 

       lists of gluten-free products.  However, when you

 

       look at those lists and you ask how they were

 

       developed, there are no standards for developing

 

       those lists.

 

                 DR. HEIMBURGER:  Doug Heimburger, a follow

 

       up to that.  That is not the same, is it, as saying

 

       "gluten-free"?  Do they not want a label except it

                                                                 84

 

       is gluten-free with a consistent and clear

 

       definition of that?

 

                 MS. KUPPER:  They do want a label that

 

       says gluten-free with a clear and consistent

 

       definition.

 

                 DR. HEIMBURGER:  Yes.

 

                 MS. KUPPER:  I believe that gluten-free is

 

       not is not going to mean zero; it can't mean zero.

 

                 CHAIRMAN DURST:  Any further questions or

 

 

       comments?

 

                 (No verbal response.)

 

                 CHAIRMAN DURST:  Thank you very much.

 

                 CHAIRMAN DURST:  Our next speaker is

 

       Dr. Donald Kasarda, who is a consultant and retired

 

       senior scientist from the Agricultural Research

 

       Service of the USDA.  He will make a presentation

 

       on grains.

 

                                  GRAINS

 

                 DR. KASARDA:  Good morning everyone.  I am

 

       a research chemist retired from the U.S. Department

 

       of Agriculture, although I still maintain a

 

       relationship with my old lab in Albany, California,

                                                                 85

 

       as a collaborator.

 

                 Now, Dr. Murray covered a lot of the

 

       things I am going to talk about.  Maybe I will be

 

       able to add a little bit more detail to some of

 

       them, but he did an excellent job of talking about

 

       some of the grain topics.

 

                 (Slide.)

 

                 DR. KASARDA:  Immunology textbooks often

 

       classify hypersensitivities into these four types.

 

       Celiac disease is a delayed type hypersensitivity

 

       that involves T-cells in the primary mechanism.  It

 

       falls into Type IV.  Allergy is Type I and is

 

       mediated by IgE antibodies.

 

                 Now, in the case of celiac disease, it is

 

       often suggested that there is a Th1 mechanism

 

       involved in which T-cells are presented with

 

       gliadin peptides, and, ultimately produce

 

       cytokines, inflammatory cytokines such as

 

       interferon gammas as an example.

 

                 Now, in the case of allergy, however, the

 

       same molecules that can induce the symptoms of

 

       celiac disease are also capable of producing

                                                                 86

 

       allergies.  We do have a certain amount of

 

       confusion sometimes between immediate

 

       hypersensitivities and the delayed-type, celiac

 

       disease.

 

                 (Slide.)

 

                 DR. KASARDA:  Now, this is the same

 

       diagram that Dr. Murray showed.  I want to talk

 

       about primarily the endosperm, which is this white

 

       part here (indicating) in the cutaway diagram.

 

                 The starchy endosperm is made up of about

 

       75 percent starch, but it also contains about 7 to

 

       17 percent protein, depending on the use of the

 

       wheat.  Most of this protein, about 75 percent of

 

       it, is gluten protein.

 

                 The proteins are storage proteins.  They

 

       are used by the developing plant that comes from

 

       the germ here.  The germ is separated from the

 

       outer layers and the endosperm during the milling

 

       process after crushing and sieving.

 

                 The storage proteins are broken down upon

 

       germination of the seed to produce a new plant.

 

       The resulting amino acids and nitrogen are used in

                                                                 87

 

       the synthesis of new molecules needed by the

 

       developing plant.  Now, as I mentioned, about 75

 

       percent of the storage protein is, in fact, gluten

 

       protein.

 

                 (Slide.)

 

                 DR. KASARDA:  This is a picture of flour

 

       particles, a scanning electron micrograph.  These

 

       round, spherical structures are starch granules.

 

       These (indicating) are A type, there are some

 

       B types which are small here.  The surrounding

 

       rough-edged material is the gluten protein or

 

       storage protein.

 

                 (Slide.)

 

                 DR. KASARDA:  If you mix together flour

 

       and water, as most of you have had the experience,

 

       you can form a cohesive elastic dough.  If you need

 

       a dough under water, say, in a large container of

 

       water or under a stream of water, you can wash out

 

       the starch granules; they pop right out of the

 

       matrix.  You are left with a cohesive, elastic mask

 

       consisting mainly of the storage or gluten

 

       proteins.

                                                                 88

 

                 (Slide.)

 

                 DR. KASARDA:  Now, this is the traditional

 

       cereal chemist definition of gluten.  You cannot

 

       carry out this process with rye and barley.

 

       Therefore, to the traditional cereal chemist, there

 

       is no gluten in rye and barley.  However, the

 

       celiac disease community has adopted the term

 

       "gluten" for any protein that is toxic or harmful

 

       to a celiac patient.

 

                 This terminology problem sometimes is

 

       confusing when patients go to a company where they

 

       might be dealing with a traditional cereal chemist,

 

       and there is a certain amount of confusion as to

 

 

       what is gluten.  As I said, this is the traditional

 

       definition, but it has been expanded to include

 

       other grains that are harmful to celiac patients.

 

                 Now, from time to time, you will hear

 

       about these fractions of gluten.  Going way back,

 

       at least over a hundred years, it has been

 

       traditional to divide gluten into two, roughly,

 

       equal fractions based on their solubility.  This is

 

       not an exact separation.  No solubility fraction is

                                                                 89

 

       ever perfect.

 

                 Traditionally, it was alcohol-water

 

       solution and sometimes we used detergent solutions.

 

       We divide it up into the soluble fraction, which we

 

       call "gliadin."

 

                 This is made up of monomeric proteins of

 

       the prolamin class.  The prolamin terminology comes

 

       from Osbourne back around 1900.  It is derived from

 

       the fact that there are two major amino acids found

 

       in the composition of these proteins.  Proline and

 

       glutamine, hence, prolamin.

 

                 By structure, we have three types: the

 

       alpha type, gamma type, or omega types.  Sometimes

 

       people speak of the alpha/beta.  I will talk about

 

       that in a little as we go along.

 

                 Now, the insoluble fraction is called

 

       "glutenin" by the cereal chemists.  In rye and

 

       barley, there is an equivalent fraction that we

 

       called just generically "glutelin."

 

                 Now, this polymeric fraction consists of

 

       prolamin subunits.  Again, large amounts of proline

 

       and glutamine in the composition of the proteins. 

                                                                 90

 

       These subunits are linked together by disulfide

 

       bonds into a higher level of polymer.

 

                 Of course, a protein is a polymer in

 

       itself.  It is divided into two main types the

 

       low-molecular weight and the high-molecular weight

 

       glutenin subunits.

 

                 (Slide.)

 

                 DR. KASARDA:  This just is a table showing

 

       the percentages in the various types of proteins.

 

       For example, you have the sum of glutamine and

 

       proline ranging from about 40 percent up to about

 

       80 percent in some of the omega gliadins.

 

                 This is pretty unusual to have such a high

 

       percentage of glutamine and proline.  This is key

 

       to the toxicity, because the toxic sequences

 

       involve glutamine and proline and usually an

 

       aromatic as well, either tyrosine or phenylalanine.

 

                 (Slide.)

 

                 DR. KASARDA:  Now, the terminologies that

 

       we use really go back to early electrophoretic

 

       studies in the late sixties and early seventies.

 

       Again, if we follow this diagram here, this is an

                                                                 91

 

       acid gel in which the proteins are separated by an

 

       electric field in a polyacrylamide gel.

 

                 The terminology actually came from a sort

 

       of free-boundary electrophoresis that was carried

 

       out at our Northern Regional Research Center back

 

       in the sixties.  When they developed the

 

       polyacrylamide gel electrophoresis, it was found

 

       that the fractions fit with the mobility in the

 

       electrophoretic gel.

 

                 You have the alpha, fastest moving; beta;

 

       gamma; and omega.  Structurally, the alphas and

 

       betas are pretty similar.  Some people will talk

 

       about alpha/beta types.  I just lump them together

 

       as alpha types.

 

                 Now, the alpha type and gamma type are

 

       about the same size.  If you carry out SDS page or

 

       polyacrylamide gel electrophoresis in detergent,

 

       sodium dodecyl sulfate, which is a very good

 

       dissociating agent for proteins.

 

                 Reduced or unreduced the gliadins give a

 

       pattern somewhat similar to this.  It is not quite

 

       as good at resolving alpha, beta and gammas as you

                                                                 92

 

       find in the acid gels where aluminum lactate was

 

       one of the favorite buffers.

 

                 If we go over to the glutenin fraction,

 

       and these are the subunits linked together by

 

       disulfide bonds, if you try to take a purified

 

       glutenin fraction and run it into an acid gel or

 

       into a detergent gel, mostly you've just got a

 

       little bit of streaking around the origin because

 

       the polymers are too large to migrate into the gel.

 

                 (Slide.)

 

                 DR. KASARDA:  Upon reduction, however, you

 

       begin to see this type of pattern here in which

 

       there is a group of high-molecular-weight subunits

 

       and a group of low-molecular-weight subunits.  This

 

       only occurs for the glutenin fraction when you

 

       reduce the disulfide bond.

 

                 (Slide.)

 

                 DR. KASARDA:  This is a two-dimensional

 

       pattern, electrophoretic pattern, of the gluten

 

       proteins.  All you have to recognize is that each

 

       spot here represents a separated protein.  There

 

       are quite a few different gluten proteins, and we

                                                                 93

 

       can count easily 50, 60, 70 spots in such a

 

       pattern.  Therefore, there are at least 50, 60, 70

 

       gluten protein components.

 

                 We know from genomic studies that, in

 

       fact, there are probably at least a hundred genes

 

       coding for these proteins, and probably several

 

       hundred genes coding for the proteins.  The loci in

 

       the genome that code for these proteins are spread

 

       out over about nine different loci in the genome.

 

                 Now, as far as we know, all of these

 

       gluten proteins are toxic in celiac disease.  This

 

       group here (indicating) are the omega gliadins, and

 

       they seem to be particularly active.

 

                 However, all of the gluten proteins have

 

       been tested by Paul Ciclitira's group and

 

       Peter Howdle's group in the U.K., and they all

 

       indicated by direct installation into the small

 

       intestine that these proteins, all of these

 

       different classes are toxic.

 

                 These omega gliadins are noted for being

 

       strong allergen in exercise-induced anaphylaxis.

 

       They are one of the really strong antigens involved

                                                                 94

 

       in that particular allergy.

 

                 (Slide.)

 

                 DR. KASARDA:  This is a schematic diagram

 

       that illustrates the fact that all of these

 

       proteins are noted for a repetitive domain in which

 

       certain amino acid sequences are repeated over and

 

       over again.

 

                 They are somewhat degenerate, but we can

 

       derive consensus sequences.  These are glutenin

 

       subunits, gamma-type gliadins.  These red,

 

       staplelike lines indicate intramolecular disulfide

 

       bonds.

 

                 In a glutenin subunit, we also have free

 

       cysteines which can link up to another molecule to

 

       form these higher-level polymers.  For example,

 

       here is an alpha-gliadin -- I'm going to talk about

 

       this a little bit more -- the end terminal, or the

 

       first half of the molecule, is made up of these

 

       repeating sequences.

 

                 The second half is not repetitive and

 

       contains most of the disulfide bonds.  Toxicity

 

       seems pretty likely to be limited to the repeat

                                                                 95

 

       regions.  These are the high-glutamine, the

 

       high-proline regions.

 

                 Now, the omega-type gliadin seems to have

 

       lost -- well, we are not entirely sure whether they

 

       lost this type of domain or not, but in any case

 

       they are made up almost entirely of repeating

 

       sequences.

 

                 (Slide.)

 

                 DR. KASARDA:  This is a hypothetical model

 

       of the gluten polymer or glutenin in which the

 

       subunits are joined by intermolecular disulfide

 

       bonds, there are also these intramolecular

 

       disulfide bonds, to form a higher-level polymer

 

       that provides elasticity to a dough.

 

                 The gliadins and the glutenins are

 

       cohesive with one another, but the gliadins

 

       contribute more to the extensibility of the dough,

 

       and the elasticity comes primarily from the

 

       glutenin fraction.

 

                 (Slide.)

 

                 DR. KASARDA:  Now, here I show some of the

 

       types of sequences that you find in the repeats. 

                                                                 96

 

       Now, they look pretty similar, a lot of glutamine,

 

       which is represented by "Q"; a lot of proline

 

       represented by "P"; and usually an aromatic

 

       residue, either phenylalanine, "F," or tyrosine,

 

       "Y."

 

                 Somewhere, and these are often degenerate.

 

       They are not exactly according to the consensus

 

       that I show here.  Somehow along the line these

 

       sequences have acquired toxicity in celiac disease.

 

                 (Slide.)

 

                 DR. KASARDA:  Now, this is the complete

 

       sequence of an alpha gliadin.  This is the

 

       end-terminal region up here (pointing).  It starts

 

       at one, and there are 263 amino acid residues.

 

       Here, note the predominance of the blue Q's and the

 

       red P's for the proline and glutamine residues.

 

                 This half of the molecule here is the

 

       repeat region.  There is also this interesting set

 

       of glutamines, which really hasn't been studied in

 

       celiac disease.  It is probably not toxic, but, as

 

       I say, there has been almost no study of this

 

       polyglutamine stretch here.

                                                                 97

 

                 Note also these vertical lines here which

 

 

       I show.  Those are sites that we have observed

 

       where cleavages occur with gastric enzyme, pepsin

 

       and pancreatic enzymes, trypsin and chymotripsin.

 

                 Now, most proteins would be broken down by

 

       the digestive enzymes into single amino acids or

 

       very small peptides: diatride, tetrapeptides that

 

       are easily absorbed, which are probably not toxic.

 

                 (Slide.)

 

                 DR. KASARDA:  In the case, as Dr. Murray

 

       mentioned, because we have a lot of proline which

 

       interferes with the breakdown by the proteolytic

 

       enzymes, we can get some pretty large stretches.

 

       This stretch here from 31 to 55 right here is

 

       something that we have tested as toxic.

 

                 Other people have dealt with sequences

 

       from this stretch and found them also to be at

 

       given toxic.  The fact that this gliadin and

 

       glutenin proteins are difficult to digest by the

 

 

       digestive enzymes allows these toxic stretches to

 

       exist longer than you would find for other

 

       proteins.

                                                                 98

 

                 Now, this half of the molecule has a fair

 

       amount of glutamine and proline, but as far as we

 

       know toxicity does not reside in this C-terminal

 

       half or sort of the end of the molecule.  It is in

 

       sort of the forward end of the molecule.

 

                 (Slide.)

 

                 DR. KASARDA:  Now, this is what I would

 

       call my string of beads model in which I have just

 

       taken that sequence, 1 to 263, and shown it as

 

       beads on a string.

 

                 Each bead represents a different amino

 

       acid.  I tried to assign the different amino acids

 

       different code words to distinguish them.  This is

 

       the end terminal region of repeats.  This

 

       C-terminal where we have the disulfide bonds here.

 

       Toxicity resides in this part here.

 

                 This sequence here from 31 to 43 was

 

       synthesized by Mike Marsh in the U.K. first, and he

 

       instilled the synthetic peptide directly into the

 

       small intestine of several celiac patients and

 

       found changes in the mucosa that were indicative of

 

       celiac disease.  So this does seem to be a toxic

                                                                 99

 

       sequence.

 

                 Here I show a computer molecular model of

 

       what that sequence would look like in the

 

       polyproline II left-handed helical confirmation

 

       that Dr. Murray mentioned.  We think that these

 

       peptides do have a strong tendency to assume this

 

       polyproline II confirmation.

 

                 Here, I show the sequence in three-letter

 

       code as a string of beads model and here just a

 

       single-letter code.  I know most people are not

 

       used to dealing with these codes.  I apologize for

 

       using them in some of the slides, but often I am

 

       just trying to make a general point, and you don't

 

       really have to follow the sequences according to

 

       their exact correlations with the amino acids.

 

                 (Slide.)

 

                 DR. KASARDA:  Now, this is a list of some

 

       of the either toxic or immunoactive peptides that

 

       have been described in the literature.  This is

 

       from Sean, et al, from Chaitan Khosla's lab at

 

       Stanford.  The 33-Mer appears to be a very active

 

       sequence.  I have indicated some sort of homology

                                                                100

 

       here by the yellow boxes here.

 

                 All of these sequences, with the exception

 

       of this one, have been found to be toxic by direct

 

       installation into the small intestine or they have

 

       been found to stimulate T-cells, T-cell clones,

 

       derived from biopsies of celiac patients.

 

                 These are just some of the toxic

 

       sequences.  We don't know all of the toxic

 

       sequences at this point.  There are certainly

 

       others to be found, so it is a pretty complicated

 

       situation in trying to sort out exactly what it is

 

       about the sequences that produces toxicity in

 

       celiac disease.

 

 

 

                 (Slide.)

 

                 DR. KASARDA:  Now I want to move on and

 

       talk a little bit about the other grains.  If we

 

       start with the class flowering plants, which is one

 

       of the major divisions or plants in terms of

 

       taxonomy.

 

                 We go down to the major two subclasses,

 

       monocotyledones plants and dicotyledones plants. 

                                                                101

 

       We can follow the monocots down to the Gramineae or

 

       the grass family.

 

                 Here, we have only wheat, rye and barley

 

       that are toxic.  Triticale is a cross between wheat

 

       and rye, and so would be expected to be toxic.

 

                 Now, oats I have had to put in both

 

       columns, and I will explain why.  There are many

 

       other grasses in which the grains do not have toxic

 

       proteins as far as we know.

 

                 There are only two grains that have been

 

       studied with modern methods and modern approaches

 

       to understanding their relationship to celiac

 

       disease, and that is wheat and oats.

 

                 These others have often been studied very

 

       minimally including rye and barley, but rye and

 

       barley do contain proteins that have sequences

 

       quite close to those in wheat.

 

                 We assume that rye and barley are probably

 

       toxic grains according to the early results of

 

       Dicke in the Netherlands back around 1950, where

 

       they considered rye, barley and oats as part of the

 

       toxic group.

                                                                102

 

                 Now about 15 years ago, I suggested that

 

       if there are only a few grasses that contain the

 

       toxic sequences, and they are closely related as

 

       you will see, and then there are many other grasses

 

       that do not contain the toxic sequences.

 

                 I suggested that if you get into the dicot

 

       group -- the buckwheat, quinoa, amaranth, and these

 

       other grains -- it would not be toxic, simply

 

       because of their distant taxonomic relationship to

 

       wheat.

 

                 I was a little bit apprehensive about

 

       suggesting this, but over the past 15 years since I

 

       suggested this, people have been eating these other

 

       grains.  As far as I know, there hasn't been any

 

       serious indication that these do, in fact, have

 

       toxicity for celiac patients.

 

                 There have been some very fine studies

 

       from Finland and throughout the world, indicating

 

       that oats were safe for celiac patients.  But

 

       towards the end of last year the Oslo, Norway,

 

       group under Knut Lundin and Ludvig Sollid.  They

 

       have found -- well, I'm getting a little bit ahead

                                                                103

 

       of myself.  Let's deal with this slide first.

 

                 (Slide.)

 

                 DR. KASARDA:  If we take a subfamily,

 

       festucoidiae, of the grass family and we look at

 

       the tribal level, and I made this slide before the

 

       results from Oslo were published.  The hordeae --

 

       which includes wheat, rye, and barley -- were one

 

       tribe.  I thought that oats were probably

 

       non-toxic, so I put them in -- well, they belong in

 

       a separate tribe.  It was only this one tribe that

 

       had the toxic sequences.

 

                 Now, it is pretty certain that the oats

 

       are toxic to a few probably rare individuals, but

 

       we don't really know how this works out.  They

 

       found three celiac patients who definitely reacted

 

       to oats by the same mechanism that they reacted to

 

       gliadin peptides.  This, I think, was pretty well

 

       demonstrated by the work from Norway.

 

                 Now, here I show the proteins that you

 

       find in wheat, gamma-type gliadins and related

 

       low-molecular-weight glutenin subunits, they are

 

       found in rye, barley, not in oats.  Alpha-type

                                                                104

 

       gliadins are found in wheat, but you don't find

 

       them in rye and barley or in oats, and so on down

 

       the line.

 

                 Now, the avenins are a small fraction of

 

       the total proteins in oats.  These make up only

 

       about 10 percent of the protein.  Most of the

 

       protein is oat globulin, which as far as we know if

 

       not harmful or toxic to celiac patients.  There are

 

       low-molecular weight proteins related to the

 

       avenins in rye, barley, and wheat.

 

                 (Slide.)

 

                 DR. KASARDA:  Now, this is another one of

 

       those sequence slides, but let me just try to make

 

       a few points here.  This top sequence is a gliadin

 

       sequence.  It starts here (indicating) and runs

 

       down to here.

 

                 The bottom sequence is an avenin, which

 

       shows a lot of homology with the C-terminal half of

 

       this gamma-gliadin molecule.  This is also true for

 

       the alpha gliadins.  Where the amino acids are the

 

       same, I have colored them in blue.

 

                 There is a lot of homology here in the

                                                                105

 

       C-terminal half, but that is not where the toxicity

 

       lies.  The Oslo group has shown that this

 

       particular sequence, which I have underlined, does